On 11/14/24 9:17 AM, Christoph Hellwig wrote:
>> @@ -313,21 +314,35 @@ static int bio_map_user_iov(struct request *rq, struct iov_iter *iter,
>> if (unlikely(offs & queue_dma_alignment(rq->q)))
>> j = 0;
>> else {
>> - for (j = 0; j < npages; j++) {
>> + for (j = 0; j < npages; j += num_pages) {
>> struct page *page = pages[j];
>> - unsigned int n = PAGE_SIZE - offs;
>> + struct folio *folio = page_folio(page);
>> bool same_page = false;
>>
>> - if (n > bytes)
>> - n = bytes;
>>
>> - if (!bio_add_hw_page(rq->q, bio, page, n, offs,
>> - max_sectors, &same_page))
>> + folio_offset = ((size_t)folio_page_idx(folio,
>> + page) << PAGE_SHIFT) + offs;
>
> I'm not sure if Jens want to rush something like this in for 6.13, but if
> we're aiming for the next merge window I actually have a 3/4 done series
> that rips out bio_add_hw_page and all the passthrough special casing by
> simply running the 'do we need to split the bio' helper on the free-form
> bio and return an error if we do. That means all this code will go away,
> and you'll automatically get all the work done for the normal path for
> passthrough as well.
I'd rather it simmer a bit first, so I'd say we have time since 6.13 is
coming up really soon.
--
Jens Axboe
